地震救援行动的影响因素分析

从探讨救援行动的概念和响应过程出发,在分析国内外相关资料的基础上,结合我国的实际情况,分析了影响地震救援行动的方面和因素,以及它们对救援行动可能产生的影响,以期为地震救援的理论和实践提供有益的补充。     

长白山火山泥石流分布影响因子权重分析

利用层次分析法对长白山天池火山泥石流分布影响因子的权重进行了分析。将对长白山天池火山泥石流分布影响作为评价目标,将地质条件、地形地貌以及植被覆盖情况作为第一层次的评价因子,地层年代、地层岩性、风化程度、堆积厚度、高程、相对高差、纵坡比、植被类型、覆盖程度作为第二层次的评价因子,由评价目标以及2个层次的评价因子构成了层次结构模型。通过层次结构模型建立了2个层次的4个判断矩阵,通过对判断矩阵的计算,最终得到了各因子对长白山火山泥石流分布影响的权重值。其中地形地貌中的相对高差及纵坡比对长白山火山泥石流分布的影响最大。     

鸭绿江口及毗邻浅海沉积物重金属的分布特征与风险评价

采用重金属的富集系数和多金属污染度分析鸭绿江口及毗邻浅海沉积物重金属的分布特征.结果表明:鸭绿江口及毗邻浅海沉积物Cu、Hg和Cd属于重要的污染因子;多金属污染度高强度分布区与高含沙量区存在对应关系,但对重金属富集影响更大的是人类活动.采用潜在生态风险指数法与生物效应阈值浓度法2种评价方法进行研究区的生态风险评价,结果...     

复合型CoO/TiO2光催化剂降解亚甲基蓝动力学研究

以钛酸四丁酯为前驱体,采用溶胶凝胶法,制备了CoO掺杂的TiO2光催化剂。利用X射线衍射（XRD）、扫描电镜（SEM）、透射电镜（TEM）、紫外可见漫反射（UV-vis DRS）对催化剂进行了分析、表征。以中压汞灯为光源,研究了亚甲基蓝（MB）在CoO/TiO₂微粒水悬浮液中的降解动力学。结果表明：所制备的催化剂活性组分主要是锐钛矿型的二氧化钛和CoO固溶体,粒径为25～30 nm,分布均匀。亚甲基蓝的光催化降解动力学满足一级动力学,在一定的浓度范围内,反应速率常数随初始浓度增大而减少,适当的掺钴量可以有效地提高TiO₂光催化活性,其最佳掺杂量重量百分比为0.25%。     

聚硅酸锌铝的制备及其性能研究

以硅酸钠、硫酸锌、硫酸铝为原料,通过共聚法制备了无机高分子絮凝剂聚硅酸锌铝（PSZAS）,研究了Na₂SiO₃的摩尔浓度、活化时间、Al/Si、Zn/Si 配比及絮凝剂的投加量对絮凝效果的影响,用X-射线衍射（XRD）和电子扫描电镜（SEM）对该絮凝剂的结构及形貌进行了表征。结果表明：当硅酸钠的浓度为0.4 mol/L,硅酸活化时间为2 h,Si∶Al∶Zn=1∶1∶1.5,絮凝剂投加量为20 mL/L废水时,絮凝剂的电中和能力和吸附架桥能力最强,絮凝剂对含H-酸染料模拟废水的絮凝效果最好。     

In situ removal of copper from sediments by a galvanic cell

This study dealt with in situ removal of copper from sediments through an electrokinetic (EK) process driven by a galvanic cell. Iron (Fe) and carbon (C) were placed separately and connected with a conductive wire. Polluted sediments were put between them and water was filled above the sediments. The galvanic cell was thus formed due to the different electrode potentials of Fe and C. The cell could remove the pollutants in the sediments by electromigration and/or electroosmosis. Results showed that a weak voltage less than 1V was formed by the galvanic cell. The voltage decreased with the increase of time. A slight increase of sediment pH from the anode (Fe) to the cathode (C) was observed. The presence of supernatant water inhibited the variation of sediment pH because H(+) and OH(-) could diffuse into the water. The removal of copper was affected by the sediment pH and the distribution of electrolyte in sediment and supernatant water. Lower pH led to higher removal efficiency. More electrolyte in the sediment and/or less electrolyte in the supernatant water favored the removal of copper. The major removal mechanism was proposed on the basis of the desorption of copper from sediment to pore solution and the subsequent electromigration of copper from the anode to the cathode. The diffusion of copper from sediment to supernatant water was negligible.     

Fe-厌氧微生物体系降解2,4,6-三氯酚

采用Fe-厌氧微生物体系降解2,4,6-三氯酚(2,4,6-TCP).在初始pH 7.0、Fe加入量10.0 g/L、以甲酸钠为碳源的条件下,2,4,6-TCP降解效果最好.采用Fe-厌氧微生物体系降解2,4,6-TCP,比单独采用Fe或厌氧微生物体系具有明显的效果,运行60h后2,4,6-TCP开始降解,108h后2,4,6-TCP降解完全.添加2-溴乙烷磺酸盐可抑制产甲烷菌的活性,能有效促进2,4,6-TCP的降解.     

Occurrence of benzotriazoles (BTRs) in indoor air from Albany,New York,USA, and its implications for inhalation exposure

Despite the widespread use of benzotriazoles as corrosion inhibitors in many household goods, studies on the occurrence of these compounds in indoor air are scarce. In this study, five benzotriazole derivatives were measured in 83 indoor air samples collected from various locations in Albany, New York, USA. Benzotriazoles were found in a majority of the indoor air samples, and the concentrations of their sum in bulk (vapor plus particulate phases) indoor air ranged from below the method limit of quantification to 492 ng·m^?3 (geometric mean: 5.8 ng·m^?3). The highest geometric mean concentration was found in air samples collected in parking garages (155 ng·m^?3), followed by barbershops (13.6), public places (11.5), auto repair shops (5.2), automobiles (4.5), homes (4.5), offices (3.7), and laboratories (2.8). Inhalation exposure to benzotriazoles was calculated on the basis of the measured geometric mean concentrations and air inhalation rate. The highest exposure dose was found for teenagers, with a geometric mean inhalation exposure dose of 79 ng·day^?1. The body-weight normalized exposure dose, however, was the highest for infants, at 3.2 ng·(kg bw)^?1·day^?1.     

Hexabromocyclododecanes in soils and plants from a plastic waste treatment area in North China: occurrence,diastereomer- and enantiomer-specific profiles,and metabolization

Plastic waste is a source of organic contaminants such as hexabromocyclododecanes (HBCDs). HBCDs have been found to cause developmental and reproductive toxicity; it is important to investigate the occurrence and metabolization of HBCDs in the soil environments with plastic waste contamination. This work analyzed HBCDs and their metabolites in soil and plant samples collected from Xinle and Dingzhou—the major plastic waste recycling centers in North China. Results showed that total HBCD concentrations in soils followed the order: plastic waste treatment site (11.0–624 ng/g) > roadside (2.96–85.4 ng/g) ≥ farmland (8.69–55.5 ng/g). HBCDs were detected in all the plant samples with total concentrations ranging from 3.47 to 23.4 ng/g. γ-HBCD was the dominant congener in soils, while α-HBCD was preferentially accumulated in plants. Compositions of HBCD isomers in soils and plants were significantly different (P < 0.05) among sampling sites and among plant species. HBCDs in farmland soil and all plant samples exhibited high enantio-selectivity based on the enantiomeric fractions (EFs). Furthermore, metabolites of pentabromocyclododecenes (PBCDEs) were frequently identified in soils, and mono-OH-HBCDs were the most common ones in plants. This study for the first time provides evidences of HBCD contamination in the soil-plant system caused by plastic waste, their stereo-selectivity, and metabolization behavior, improving our understanding of the environmental behavior and fate of HBCDs.     

De novo formation of dioxins from milled model fly ash

Environmental Science and Pollution Research - Municipal solid waste incineration (MSWI) fly ash has been classified as hazardous waste and needs treatment in an environmentally safe manner....